1. Field of the Present Invention
The present invention is an aqueous adhesive composition comprising an N-vinyl lactam polymeric resin (e.g., a copolymer of the N-vinyl lactam and an ethylenically unsaturated monomer), a tackifier for such resin, and an effective amount of an emulsion stabilizer for the resin and tackifier to aid in cleaning metallic machine parts to which adhesive residue might become attached.
2. Description of Related Development
In copending U.S. Ser. No. 825,417, filed Feb. 3, 1986, entitled "Liquid Dispenser with Absorbent Applicator Tip", a dispensing apparatus for liquids is described which comprises a generally tubular container adapted to hole the liquid to be dispensed, the container comprising a reservoir section, a more narrow capillary section, and a frangible tip portion attached to the capillary section. The tubular container is described as being covered at its tip portion, capillary section and adjacent container reservoir section by an absorbent swab member. In a preferred commercial embodiment, the tubular container is formed of a non-polar polymeric material, such as polypropylene, whereas the absorbent swab member is formed of a cellulosic material, such as cotton. In order to manufacture substantial quantities of such dispensers, a high-speed manufacturing procedure is needed which utilizes machinery having metallic parts. In order to ensure the adequate bonding of the absorbent swab member to the non-polar polymeric surface of the dispenser, an adhesive having certain characteristics is needed, especially when one considers that it is also desirable that the adhesive composition not unduly foul the metallic surfaces of the machinery used in such a manufacturing process. Briefly stated, the adhesive needs to have sufficient wet-tack to ensure the secure attachment of the absorbent swab on the tubular polymer body. The adhesive must have good bonding characteristics to both non-polar polymeric surfaces, as well as cellulosic material in order to be effective. The adhesive must also be one which does not unduly foul metallic surfaces on the machinery in such a way as to render their cleaning difficult. Also, in order not to foul the manufacturing environment, it is preferable that the adhesive be an aqueous dispersion system.
The foregoing characteristics, which have been described for an adhesive for the aforementioned type of dispenser, are also applicable to other types of articles where a cellulosic material needs to be bonded to a non-polar polymeric surface. For example, it is known to manufacture swabs using an applicator stick formed of a plastic, such as polypropylene, with the applicator swab being cotton. The adhesive which is the subject of the present invention would also find utility in the fabrication of such swab products on appropriate swab-forming machinery.